Today, ceramic paving, in particular ceramic tiles, is usually laid using the so-called thin-bed method, in which the ceramic paving is laid in a thin, adhesive layer of tile mortar. This method, which is satisfactory for interior applications, is problematic when ceramic paving is to be laid in an exterior area, because the effects of moisture and temperature on paving of this kind frequently result in the gradual destruction of the tiles or the base in which they are laid, and it becomes impossible to avoid the diminished reliability of this type of paving, with the result that costly repair work may be required. Moisture that penetrates through the tile paving into the substratum frequently results in damage to the building itself because the moisture cannot escape easily. This occurs frequently in the case of balconies that are to be sealed.
In addition to the foregoing, it is difficult to control the crack behaviour of the ceramic paving and of the substratum because of the very different coefficients of expansion of the substratum, the thin-bed mortar, and the ceramic paving, which are brought about by the very high temperature differences between the high temperatures caused by solar radiation and the low temperatures caused by frost that occur in the exterior area. For this reason, there is frequently cracking in the tile paving if it is joined rigidly to the substratum.
For this reason, it has frequently been proposed that ceramic paving of this type that is laid in an exterior area can be laid in a more durable fashion in that the ceramic paving is deliberately decoupled from the substratum. It is true that such decoupling ensures that mechanical decoupling is effected transversely to the area that is paved; it also entails the disadvantage that the mechanical load-bearing capacity of the tile paving is inadequate. On the one hand, the tiles are not anchored firmly enough to the decoupling system, and on the other hand, the pressure strength of the decoupling system itself is not optimal.
This type of configuration for a decoupling and sealing system is described in DE 100 60 751 C1. In this configuration, what is proposed is a decoupling and sealing system that has a plastic or bitumen layer underneath, above which are disposed a first non-woven layer that is of a first hydrophobic polymer; above this there is a drainage layer that is of a second hydrophobic polymer, and then, above this, a second non-woven layer that is of the first hydrophobic polymer. It is true that, within certain limits, this layered construction permits moisture that has penetrated to drain out of the substratum of a tile layer; however, the mechanical load-bearing capacity of a layered, construction of this kind is unsatisfactory since embedding the uppermost non-woven layer in the tile mortar does not permit adequate anchoring or reinforcing function. The drainage layer is in the form of a lattice-type layer, although no exact details for forming the lattice-type layer are provided.
For this reason, it is the objective of the present invention to so develop a multilayer decoupling and sealing system of this type such that an improvement of the mechanical load-bearing capacity and anchoring to the tile layer can be achieved.
This objective has been achieved by the distinguishing features set out in Patent Claim 1 in conjunction with the features set out in the preamble. Further advantageous embodiments of the present invention are set out in the secondary claims.